This application relates generally to mechanically assisted circulation (MAC) systems, and more specifically relates to improved methods and systems for generating alarms based on fault detections in a MAC system. Such alarms can relate to an implantable blood pump of an MAC system as well as to power sources for the blood pump.
Ventricular assist devices, known as VADs, are implantable blood pumps used for both short-term (i.e., days, months) and long-term applications (i.e., years or a lifetime) where a patient's heart is incapable of providing adequate circulation, commonly referred to as heart failure or congestive heart failure. According to the American Heart Association, more than five million Americans are living with heart failure, with about 670,000 new cases diagnosed every year. People with heart failure often have shortness of breath and fatigue. Years of living with blocked arteries or high blood pressure can leave your heart too weak to pump enough blood to your body. As symptoms worsen, advanced heart failure develops.
A patient suffering from heart failure, also called congestive heart failure, may use a VAD while awaiting a heart transplant or as a long term destination therapy. In another example, a patient may use a VAD while recovering from heart surgery. Thus, a VAD can supplement a weak heart (i.e., partial support) or can effectively replace the natural heart's function. VADs can be implanted in the patient's body and powered by an electrical power source inside or outside the patient's body.
In view of the critical nature of the support provided by a MAC system, close monitoring of the MAC system may be used to detect faults within the MAC system that, if not suitably addressed in time, may result in failure of the MAC system that may endanger the life of the patient. For example, monitoring of an implanted blood pump may detect a fault condition that is likely to worsen over time, thereby requiring corrective action to be taken before the fault condition becomes critical. As another example, fault conditions within a power supply system, such as low power states and/or disconnects may be detected and communicated to the patient so that the patient can take appropriate action to avoid a critical loss of power supply to the MAC system.
Close monitoring, however, can result in the detection of transient faults, which if communicated to the patient can result in the patient being subjected to undue stress. Such communication of transient faults to the patient may even result in the patient failing to take necessary action when subsequently informed of an actual critical fault.
Moreover, power is often supplied to an implantable blood pump via redundant power sources so as to decrease the probability of power interruption to the blood pump. The use of multiple power sources, however, increases the number of power source component faults that may occur, thereby increasing the number of potential faults for a patient to contend with.
Accordingly, improved approaches for monitoring MAC systems such that communication with the patient is undertaken that is appropriate in view of the condition of the MAC system are desirable.